org.json.JSONException: JSONArray[0] is not a JSONObject - Java

Hello I am trying to read and parse a JSON file, when I attempt to read it I got exception of =org.json.JSONException: JSONArray[0] is not a JSONObject. The JSON is shorten for sake of example. Provided will be my code,json and desired output.

Code:

public void Trial () throws JSONException {
		String json = "[[{"appId": "MBSP","askPrice": 0,"bidPrice": 0,"collectionDataSource": "ExternalTick","collectionName": "FRM_MBS_TBA_FN_15Y_0.03_FWD0","collectionObservationTime": "2020-09-21T17:47:59.703Z","collectionType": "LIVE","coupon": 1.03,"createdBy": "Test","createdOn": "2020-09-21T17:47:59.703Z","createdOnDate": 0,"forward": 0,"issuingAgency": "FF","lastUpdated": "2020-09-21T17:47:59.703Z","lastUpdatedBy": "string","lastUpdatedDate": 0,"maturity": ,"midPrice":0 ,"mtaVersionNumber": 0,"settlementDate": "2020-09-21T17:47:59.703Z"}]]
 ";
		JSONArray jsonObj = new JSONArray(json);
		for (int i = 0; i < jsonObj.length(); i++) {
		    JSONObject jsonobject = jsonObj.getJSONObject(i);
		    String Coupon = jsonobject.getString("Coupon");
		    System.out.println(Coupon);
		}
	}

JSON:

[[
  {
    "appId": "MBSP",
    "askPrice": 0,
    "bidPrice": 0,
    "collectionDataSource": "ExternalTick",
    "collectionName": "FRM_MBS_TBA_FN_15Y_0.03_FWD0",
    "collectionObservationTime": "2020-09-21T17:47:59.703Z",
    "collectionType": "LIVE",
    "coupon": 1.03,
    "createdBy": "Test",
    "createdOn": "2020-09-21T17:47:59.703Z",
    "createdOnDate": 0,
    "forward": 0,
    "issuingAgency": "FF",
    "lastUpdated": "2020-09-21T17:47:59.703Z",
    "lastUpdatedBy": "string",
    "lastUpdatedDate": 0,
    "maturity": ,
    "midPrice":0 ,
    "mtaVersionNumber": 0,
    "settlementDate": "2020-09-21T17:47:59.703Z"
  }
]]

Wanted ooutput

 1.03

Any help would be appreciated.

The valid JSON should be :

[
  {
    "appId": "MBSP",
    "askPrice": 0,
    "bidPrice": 0,
    "collectionDataSource": "ExternalTick",
    "collectionName": "FRM_MBS_TBA_FN_15Y_0.03_FWD0",
    "collectionObservationTime": "2020-09-21T17:47:59.703Z",
    "collectionType": "LIVE",
    "coupon": 1.03,
    "createdBy": "Test",
    "createdOn": "2020-09-21T17:47:59.703Z",
    "createdOnDate": 0,
    "forward": 0,
    "issuingAgency": "FF",
    "lastUpdated": "2020-09-21T17:47:59.703Z",
    "lastUpdatedBy": "string",
    "lastUpdatedDate": 0,
    "maturity": 0,
    "midPrice":0 ,
    "mtaVersionNumber": 0,
    "settlementDate": "2020-09-21T17:47:59.703Z"
  }
]

Update the code as well :

public class Sample {

	public static void main(String[] args) {
		String json = "[{\n" + 
				"	\"appId\": \"MBSP\",\n" + 
				"	\"askPrice\": 0,\n" + 
				"	\"bidPrice\": 0,\n" + 
				"	\"collectionDataSource\": \"ExternalTick\",\n" + 
				"	\"collectionName\": \"FRM_MBS_TBA_FN_15Y_0.03_FWD0\",\n" + 
				"	\"collectionObservationTime\": \"2020-09-21T17:47:59.703Z\",\n" + 
				"	\"collectionType\": \"LIVE\",\n" + 
				"	\"coupon\": 1.03,\n" + 
				"	\"createdBy\": \"Test\",\n" + 
				"	\"createdOn\": \"2020-09-21T17:47:59.703Z\",\n" + 
				"	\"createdOnDate\": 0,\n" + 
				"	\"forward\": 0,\n" + 
				"	\"issuingAgency\": \"FF\",\n" + 
				"	\"lastUpdated\": \"2020-09-21T17:47:59.703Z\",\n" + 
				"	\"lastUpdatedBy\": \"string\",\n" + 
				"	\"lastUpdatedDate\": 0,\n" + 
				"	\"maturity\": 0,\n" + 
				"	\"midPrice\": 0,\n" + 
				"	\"mtaVersionNumber\": 0,\n" + 
				"	\"settlementDate\": \"2020-09-21T17:47:59.703Z\"\n" + 
				"}]";
		JSONArray jsonObj = new JSONArray(json);
		for (int i = 0; i < jsonObj.length(); i++) {
			JSONObject jsonobject = jsonObj.getJSONObject(i);
			double Coupon = jsonobject.getDouble("coupon");
			System.out.println(Coupon);
		}
	}

}

Output :

1.03

if you check again your json you will notice there is array in array and then object.
[ [ { } ] ]

Try this input, [ { } ]

[
{
"appId": "MBSP",
"askPrice": 0,
"bidPrice": 0,
"collectionDataSource": "ExternalTick",
"collectionName": "FRM_MBS_TBA_FN_15Y_0.03_FWD0",
"collectionObservationTime": "2020-09-21T17:47:59.703Z",
"collectionType": "LIVE",
"coupon": 1.03,
"createdBy": "Test",
"createdOn": "2020-09-21T17:47:59.703Z",
"createdOnDate": 0,
"forward": 0,
"issuingAgency": "FF",
"lastUpdated": "2020-09-21T17:47:59.703Z",
"lastUpdatedBy": "string",
"lastUpdatedDate": 0,
"maturity": ,
"midPrice":0 ,
"mtaVersionNumber": 0,
"settlementDate": "2020-09-21T17:47:59.703Z"
}
]

Another way is handle in code to access json array inside a
json array to get json object.

Thanks, I hope that helps you.

Your JSON input seems invalid:

• No [[...]]
• "maturity": , maybe not valid json node
• code String Coupon = jsonobject.getString("Coupon"); not correct

Solution:

• Update JSON input like. [...]
• Update maturity to a valid even value is empty/null
• Change you code to String coupon = jsonobject.getString("coupon");